Jeremy didn't " play anything up ". If you read Cal's book,it has connotations of him having been a " go-between " in the family,particularly when his mother repeated " why can't you be like Jeremy " as she'd referred to Sheila and her marriage to Colin,then the divorce not long after. The anger and guilt that Sheila was constantly made to feel knew no bounds,as even Jeremy felt the guilt by his mother repeating these comparisons. This always drove Sheila mad with anger-----------as it naturally would when a parent always makes comparisons.